Which of these are measures of quantity?

3 moles of sand grains on a beach

25-pound bag of sugar

16 gigabytes of memory

2-liter bottle of soda

radioactive decay occurs in unstable atomic nuclei – that is, ones that don't have enough binding energy to hold

the nucleus together due to an excess of either protons or neutrons.

explanation: it gains negative electrons, therefore becoming negatively charged. as charge cannot be created, nor destroyed, only transferred, this leaves the wool positive. now that they have opposite charges, the two items attract.